init project

test/regressions/fixtures/GlobalStyles/InjectFirst.js

@@ -0,0 +1,16 @@
+import * as React from 'react';
+import { StyledEngineProvider } from '@mui/material/styles';
+import CssBaseline from '@mui/material/CssBaseline';
+import GlobalStyles from '@mui/material/GlobalStyles';
+import Typography from '@mui/material/Typography';
+
+export default function InjectFirst() {
+  return (
+    <StyledEngineProvider injectFirst>
+      <CssBaseline />
+      <Typography variant="h1">Hello MUI v6</Typography>
+      <Typography>The color should be red</Typography>
+      <GlobalStyles styles={() => ({ body: { color: 'red' } })} />
+    </StyledEngineProvider>
+  );
+}